The use of flexible containers is increasingly common. In the past the so called "pillow" pouches were used which had the shape of a pillow, but nowadays what are referred to as "stand up pouches" are used. These pouches have one end which in the case of a full pouch becomes substantially circular and therefore stands up. These types of pouches are able to be displayed better than the pillow pouches. Flexible containers or pouches are seen as being environmentally acceptable where the rigid bottles and containers of the prior art are not or, at least, present difficulties in disposal. It is therefore quite common to have liquids of a wide variety packed in flexible pouches or containers. There are simple instructions printed on the container to cut off the corner or slit the corner to pour the contents from the container.
There are a number of disadvantages. The storage of liquid in an opened flexible container can be a nuisance. Typically, it is necessary to pour the unused liquid into a more rigid container. Indeed, the primary application for the flexible, stand-up pouch is for refilling liquid products into the original, rigid container. The consumer is encouraged to refill and reuse the existing, original container. This significantly reduces the plastic content, and the bulk content of garbage for disposal at municipal landfill sites.
A further disadvantage is when the flexible pouches are used for engine oil. This has not been well received at filling stations as the attendant cannot leave the flexible pouch in the engine oil inlet. Instead the attendant must stand by the vehicle. The prior art oil containers permitted the attendant to open a rigid container of oil, insert the neck into the oil inlet and leave it there while, for example, the attendants checks the tires or controls the gas pump.
There have been a number of suggestions to cure this problem. Dilworth in U.S. Pat. No. 5,224,619 teaches a container having a spike in the bottom. The idea is to place a frangible pouch within the jug. The spike pierces the pouch and the content then runs into the jug from the frangible pouch.
Gray in U.S. Pat. No. 3,974,912 teaches the holding of a pouch within a frame. Knife blades can be moved in the frame to cut the pouch. The liquid from the pouch then pours out through a funnel. As can be seen this device requires many steps to perform the end result.
Of the above devices, Dilworth et al. is believed to have the disadvantage that the frangible container being retained in the jug is potentially messy. The container must be removed at some stage. The device patented by Gray is fairly elaborate.